rosdep command not found solution

I am trying to use rosdep to install some packages, but ros told me 'rosdep command not found', here is the solution

1. open ubuntu software center, select ROS precise (if you have followed the instruction to install ros)

2.search rosdep, you will find 'rosdep system dependency installation too', install this one

3.run the command 'sudo rosdep init' and 'rosdep update'

4.test rosdep, and it will work

good luck~~